X-Git-Url: http://git.zerfleddert.de/cgi-bin/gitweb.cgi/proxmark3-svn/blobdiff_plain/13d77ef964cefe68750873d5268299a53c9e22a5..40762506601062bb79a0a081a7b508b8e02c29fa:/common/lfdemod.c

diff --git a/common/lfdemod.c b/common/lfdemod.c
index 5b0bc29d..3305c8b0 100644
--- a/common/lfdemod.c
+++ b/common/lfdemod.c
@@ -97,6 +97,7 @@ uint8_t Em410xDecode(uint8_t *BitStream, size_t *size, size_t *startIdx, uint32_
   for (uint8_t extraBitChk=0; extraBitChk<5; extraBitChk++){
     errChk = preambleSearch(BitStream+extraBitChk+*startIdx, preamble, sizeof(preamble), size, startIdx);
     if (errChk == 0) return 0;
+	if (*size<64) return 0;
     if (*size>64) FmtLen = 22;
     if (*size<64) return 0;
     idx = *startIdx + 9;
@@ -375,34 +376,39 @@ int cleanAskRawDemod(uint8_t *BinStream, size_t *size, int clk, int invert, int
 			smplCnt++;
 		} else if (BinStream[i] <= low && !waveHigh){
 			smplCnt++;
-		} else { //not high or low or a transition
-			if (smplCnt > clk-(clk/4)) { //full clock
-				if (smplCnt > clk + (clk/4)) { //too many samples
-					errCnt++;
-					BinStream[bitCnt++]=77;
-				} else if (waveHigh) {
-					BinStream[bitCnt++] = invert;
-					BinStream[bitCnt++] = invert;
-				} else if (!waveHigh) {
-					BinStream[bitCnt++] = invert ^ 1;
-					BinStream[bitCnt++] = invert ^ 1;
-				}
-				waveHigh ^= 1;  
-				smplCnt = 0;
-			} else if (smplCnt > (clk/2) - (clk/5)) {
-				if (waveHigh) {
-					BinStream[bitCnt++] = invert;
-				} else if (!waveHigh) {
-					BinStream[bitCnt++] = invert ^ 1;
+		} else { //transition
+			if ((BinStream[i] >= high && !waveHigh) || (BinStream[i] <= low && waveHigh)){
+				if (smplCnt > clk-(clk/4)-1) { //full clock
+					if (smplCnt > clk + (clk/4)+1) { //too many samples
+						errCnt++;
+						BinStream[bitCnt++]=77;
+					} else if (waveHigh) {
+						BinStream[bitCnt++] = invert;
+						BinStream[bitCnt++] = invert;
+					} else if (!waveHigh) {
+						BinStream[bitCnt++] = invert ^ 1;
+						BinStream[bitCnt++] = invert ^ 1;
+					}
+					waveHigh ^= 1;  
+					smplCnt = 0;
+				} else if (smplCnt > (clk/2) - (clk/4)-1) {
+					if (waveHigh) {
+						BinStream[bitCnt++] = invert;
+					} else if (!waveHigh) {
+						BinStream[bitCnt++] = invert ^ 1;
+					}
+					waveHigh ^= 1;  
+					smplCnt = 0;
+				} else if (!bitCnt) {
+					//first bit
+					waveHigh = (BinStream[i] >= high);
+					smplCnt = 1;
+				} else {
+					smplCnt++;
+					//transition bit oops
 				}
-				waveHigh ^= 1;  
-				smplCnt = 0;
-			} else if (!bitCnt) {
-				//first bit
-				waveHigh = (BinStream[i] >= high);
-				smplCnt = 1;
-			} else {
-				//transition bit? ignore
+			} else { //haven't hit new high or new low yet
+				smplCnt++;
 			}
 		}
 	}
@@ -888,16 +894,18 @@ int PyramiddemodFSK(uint8_t *dest, size_t *size)
 
 uint8_t DetectCleanAskWave(uint8_t dest[], size_t size, int high, int low)
 {
-	uint8_t allPeaks=1;
+	uint16_t allPeaks=1;
 	uint16_t cntPeaks=0;
-	for (size_t i=30; i<255; i++){
+	size_t loopEnd = 572;
+	if (loopEnd > size) loopEnd = size;
+	for (size_t i=60; i<loopEnd; i++){
 		if (dest[i]>low && dest[i]<high) 
 			allPeaks=0;
 		else
 			cntPeaks++;
 	}
-	if (allPeaks==0){
-		if (cntPeaks>210) return 1;
+	if (allPeaks == 0){
+		if (cntPeaks > 300) return 1;
 	}
 	return allPeaks;
 }
@@ -939,10 +947,12 @@ int DetectStrongAskClock(uint8_t dest[], size_t size)
 			}
 		}
 	}
+	uint8_t tol;
 	for (idx=8; idx>0; idx--){
-		if (clk[idx] >= highCnt && clk[idx] <= highCnt+2)
+		tol = clk[idx]/8;
+		if (clk[idx] >= highCnt - tol && clk[idx] <= highCnt + tol)
 			return clk[idx];
-		if (clk[idx] >= highCnt2 && clk[idx] <= highCnt2+2)
+		if (clk[idx] >= highCnt2 - tol && clk[idx] <= highCnt2 + tol)
 			return clk[idx];
 	}
 	return -1;
@@ -1742,22 +1752,22 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
   //find first phase shift
   for (i=0; i<loopCnt; i++){
     if (dest[i]+fc < dest[i+1] && dest[i+1] >= dest[i+2]){
-      waveEnd = i+1;
-      //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
-      waveLenCnt = waveEnd-waveStart;
+        waveEnd = i+1;
+        //PrintAndLog("DEBUG: waveEnd: %d",waveEnd);
+        waveLenCnt = waveEnd-waveStart;
       if (waveLenCnt > fc && waveStart > fc){ //not first peak and is a large wave 
         lastAvgWaveVal = avgWaveVal/(waveLenCnt);
-        firstFullWave = waveStart;
-        fullWaveLen=waveLenCnt;
-        //if average wave value is > graph 0 then it is an up wave or a 1
+          firstFullWave = waveStart;
+          fullWaveLen=waveLenCnt;
+          //if average wave value is > graph 0 then it is an up wave or a 1
         if (lastAvgWaveVal > 123) curPhase^=1;  //fudge graph 0 a little 123 vs 128
-        break;
-      } 
+          break;
+        } 
       waveStart = i+1;
       avgWaveVal = 0;
-    }
+      }
     avgWaveVal+=dest[i+2];
-  }
+    }
   //PrintAndLog("DEBUG: firstFullWave: %d, waveLen: %d",firstFullWave,fullWaveLen);  
   lastClkBit = firstFullWave; //set start of wave as clock align
   //PrintAndLog("DEBUG: clk: %d, lastClkBit: %d", *clock, lastClkBit);
@@ -1779,7 +1789,7 @@ int pskRawDemod(uint8_t dest[], size_t *size, int *clock, int *invert)
         waveEnd = i+1;
         waveLenCnt = waveEnd-waveStart;
         lastAvgWaveVal = avgWaveVal/waveLenCnt;
-        if (waveLenCnt > fc){  
+        if (waveLenCnt > fc){ 
           //PrintAndLog("DEBUG: avgWaveVal: %d, waveSum: %d",lastAvgWaveVal,avgWaveVal);
           //if this wave is a phase shift
           //PrintAndLog("DEBUG: phase shift at: %d, len: %d, nextClk: %d, i: %d, fc: %d",waveStart,waveLenCnt,lastClkBit+*clock-tol,i+1,fc);